Cetus (sē´-tus)—the Whale. (face Southeast.)

Location.—A line drawn from Polaris, to δ Cassiopeiæ, and prolonged two and one third times its original length, reaches the centre of this constellation.

It lies just below Aries and the Triangle, and resembles the figure of the prehistoric icthyosaurus, while some see in the outline an easy chair. The head of the beast is characterized by a clearly traced pentagon, about 20° southeast of Aries. The brightest star in the constellation is &alpha

of the second magnitude. It is at one apex of the pentagon, about 15° east of Al Rischa in Pisces, and 37° directly south of Algol.

The noted variable Mira also known as ο Ceti is the chief object of interest in this constellation.

It was discovered by Fabricius in 1596 and varies from the ninth magnitude to the third or fourth in a period of 334 days. It can be observed during its entire range with a 3" glass.

In 1779 Mira is reported to have been as bright as the first-magnitude star Aldebaran. It lies almost exactly on a line joining γ and ζ Ceti a little nearer the former. Ten degrees south of it are four faint stars about 3° apart forming a square.

τ Ceti is one of our nearest neighbors at a distance of nine light years.

ζ is a naked-eye double star.